A Watershed Moment for Los Angeles

This vegetated depression, or swale, helps storm water infiltrate into the earth rather than running rapidly off sidewalks and streets. While helping prevent damaging floods, bioswales can recharge local groundwater, beautify urban landscapes, and purify water all at the same time. This particular swale is in Seattle, but more may soon grace the streets of Los Angeles. Photo courtesy of US Environmental Protection Agency

The timing might seem odd, even self-destructive.

Last month, in the midst of one of the most severe droughts in California’s historical record, Los Angeles Mayor Eric Garcetti issued an executive order calling for his southern California city to cut its water imports by half within a decade.

Water transferred hundreds of miles from northern California and the Colorado River currently accounts for about 80 percent of LA’s water use, so the goal is ambitious, to say the least.

It’s also a historic turn-around. Ever since the early 20th century, when Los Angeles diverted water from the Owen’s Valley a couple hundred miles to the East – a deal made famous by the classic Roman Polanski film, Chinatown – Los Angeles has done what just about every growing western city has done: reach further and further out for more water as demands outpace supplies.

But with his bold new directive, Garcetti is writing a new script for LA’s water future.

Instead of relying on distant supplies brought in by big engineering projects, he’s banking on the idea that local supplies can meet most of the city’s water needs if they are used more efficiently and managed with more ingenuity.

Ultimately it’s about smarter water management and greater resiliency. Transferring water long distances, and especially over mountain ranges, is energy-intensive and costly. Moreover, those distant supplies are becoming less reliable. Most of LA’s imported water originates as snow in the Sierra Nevada and Colorado Rockies, and climate scientists expect those snowpacks to diminish in the coming decades.

Due to the ongoing drought, the Metropolitan Water District, which supplies Los Angeles with most of its imported water, expects to curtail supplies during the coming year.

Garcetti’s directive puts forth two other goals, as well: to reduce water use per person by 20 percent within three years, and to create an “integrated water strategy” that boosts local water supplies and improves water security. Achieving these goals is critical to meeting the water-import reduction target.

In some ways, LA’s past conservation successes make achieving these goals more difficult. Thanks to tried-and-true conservation efforts, the city’s water use today is back to where it was 40 years ago, when a million fewer people lived there.

But the Mayor’s directive acknowledges an important truth: that the city has barely scratched the surface of water conservation’s potential to meet future water needs cost-effectively and sustainably.

For one, Angelenos can reap substantial water savings by choosing more sensible, climate-appropriate vegetation. Landscape irrigation accounts for more than half of LA’s residential water use.

The mayor’s plan calls for increasing rebates for residential turf removal, giving property owners an incentive to switch from thirsty lawns to drought-tolerant vegetation. It also calls for 85% of public golf course acreage to be irrigated with recycled water by 2017, saving higher-quality potable water for drinking, showering and other household uses.

To increase local supplies, Los Angeles will look toward rainwater harvesting, stormwater capture and other techniques that prevent precipitation from running off impervious streets and pavement instead of recharging groundwater, increasing soil moisture, or being stored for other uses. A one-inch rain event in Los Angeles County can generate more than 10 billion gallons of stormwater runoff – most of which will flow, along with the urban trash and pollution it is carrying, into the Pacific Ocean.

Gardens on rooftops, vegetated swales in parking lots, and other types of “green infrastructure” help turn storm water into an asset rather than a problem.

A study of urbanized southern California and the San Francisco Bay Area, conducted by the Natural Resources Development Council and the University of California at Santa Barbara, found that rooftop rainwater capture combined with increased stormwater infiltration to recharge groundwater could increase water supplies by up to 405,000 acre-feet (132 billion gallons) within two decades.

There’s no big silver bullet in the Mayor’s plan. It’s a portfolio of actions to build water security, self-reliance and long-term sustainability. It’s also the look of urban water management in the 21st century.

Much of the world will be watching.

Sandra Postel is director of the Global Water Policy Project, Freshwater Fellow of the National Geographic Society, and author of several books and numerous articles on global water issues.  She is co-creator of Change the Course, the national freshwater conservation and restoration campaign being piloted in the Colorado River Basin.

Sandra Postel is director of the Global Water Policy Project and author of Replenish: The Virtuous Cycle of Water and Prosperity. From 2009-2015, she served as Freshwater Fellow of the National Geographic Society. Sandra is also co-creator of Change the Course, the national water stewardship initiative awarded the 2017 US Water Prize for restoring billions of gallons of water to depleted rivers and wetlands. The recipient of several honorary degrees, she works to bridge science, policy, and practice to promote innovative ways of securing water to meet both human and ecosystem needs.
  • Russ Cohen

    Hi Sandra – thanks for this posting, and for sharing this encouraging news. I must share with you, though, my observations on a recent trip to Palm Springs, CA to visit relatives. There we saw irrigation systems spraying water in the middle of the day (thus most of it is lost to evaporation and never reaches the roots of the plants intended to be watered) and/or systems that directed the spray over pavement, where (once again) it missed its intended target. Furthermore, many areas being irrigated were thin strips of manicured lawn between gated community walls and the street. It would have been much better to see those strips devoted to a more appropriate land cover. So, while I commend LA’s political leadership for promoting water conservation, I hope that the Palm Springs/Palm Desert area follows their lead.

    • Hi Russ, I couldn’t agree more. Palm Springs has one of the highest per capita water use rates in the country. — Sandra

  • Daniel Ferra

    We need to change our Energy and Water policies in order to address our Crisis and become Sustainable. A California Residential Feed in Tariff would allow homeowners to sell their Renewable Energy back to the utility, protecting our communities from grid failures, natural disasters, toxic natural gas and oil Fracking. It would also create a new revenue stream for the Hard Working Taxpaying, Voting, Homeowner.

    No one is fighting for the Hard Working, Taxpaying, Voting, Homeowner, we can change that with a Ca. Residential Feed in Tariff Energy policy that allows everyone to participate. Homeowner’s, Small and Large Businesses, Small and Large farmers, and Industries, have the right to sell Renewable Energy electricity back to the utility.

    California, there is enough Residential Solar to power 2.25 San Onofres, couple that with a Commercial Feed in Tariff and we can solve some of these environmental and electrical generating problems.

    This petition will ask the California Regulators and Law makers to allocate Renewable Portfolio Standards to Ca. Home Owners for a Residential Feed in Tariff, the RPS is the allocation method that is used to set aside a certain percentage of electrical generation for Renewable Energy in the the State. The State of California has mandated that 33% of its Energy come from Renewable Energy by 2020.

    California Energy and Water Consumption an a Ban Fracking song

    Sign and Share for a Ca. Residential Feed in Tariff. Go to the youtube site, look six inches below video, click on Show More, then click on blue link to sign the petition.

    Attachments area
    Preview YouTube video We Need To Ban Fracking.

  • John Hulburd

    Great to see your name again on important news, Ms Postel!
    What about Golf Courses (the Coachella Valley has, I believe, 115 now)? Will they be outlawed (wishful thinking on my part)?

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